18" Wide Angle; Clip-On. 17 3/4" viewing area. Wide angle rearview mirror provides a wider field of view reducing blind spots. Easy installation; no tools required simply clip on to existing rearview mirror. Chrome plated glass is shatter proof and reduces glare. The reflective chrome layer is plated on the front of the glass resulting in less distortion. Does not have the day/night switch. Objects in mirror are closer than they appear to be. Marked for off-road use only. Fits most standard rearview mirrors, recommended for use in mid-size and larger vehicles. May reduce access to mirror accessories such as map lights, compasses, OnStar controls, etc.